1. Technical Field
The present disclosure relates to image analysis, and more particularly to systems and methods for identification of targets in multispectral imaging data.
2. Discussion of Related Art
Multispectral fluorescence imaging techniques, such as fluorescence microscopy and bioluminescence, provide a mechanism for visualizing and studying molecular targets both in vitro and in vivo. These optical imaging technologies have several biomedical applications, including the diagnosis and monitoring of disease, studying the effects of drug candidates on target pathologies, and the discovery and development of biomarkers.
In multispectral fluorescence imaging, multiple targets of interest (TOIs) in a specimen are each specifically labeled with a fluorophore, which is a fluorescent molecule. The specimen is illuminated with light of a specific wavelength(s), which is absorbed by the fluorophores, causing the fluorophores to emit different wavelengths of light (e.g., longer wavelengths). These different wavelengths correspond to a different color than the absorbed light. The illumination light is separated from the weaker emitted fluorescence through the use of an emission filter. Multiple filters may be used to differentiate between the emissions of the fluorophores. The filtered emitted light for each fluorophore is converted into a digital image corresponding to a labeling pattern of the fluorophore within the specimen. The images acquired typically include intensity data, where the intensity of each pixel (e.g., on a scale of black to white) represents a level of fluorescence detected at that point in the specimen.
In multispectral fluorescence imaging, using W emission filters generates W corresponding images to output one image per fluorophore. Since the image acquisition is typically rapid, the W images may be registered to within a few pixels.
Labeled TOIs in multispectral fluorescence imaging data emit light at narrow, specific wavelengths that exclude emission from other components in the specimen. Many specimens (including samples of biological origin) frequently contain unpredictable material with which the fluorophores may bind, causing emission that passes through the specific filter, producing spurious intensity in the image. Additionally, some specimens exhibit inherent fluorescence that can be detected at the target emission wavelengths. Such situations could result in a false prediction of the presence of the TOIs. Additionally, several factors such as noise, occlusion, photobleaching, etc., can prevent a TOI from emitting a sufficient amount of light at the detected emission wavelength.
Therefore, a need exists for a system and method for distinguishing an emission indicating the presence of the TOIs from an emission that does not indicate the presence of the TOIs.